A conventional internal combustion engine that has a variable valve operating mechanism that can maintain at least one of an intake valve and an exhaust valve in a closed state is disclosed, for example, in Patent Document 1. According to this conventional internal combustion engine, a configuration is adopted so that, when a fuel-cut operation is performed in a situation in which the temperature of an exhaust purification catalyst that is arranged in an exhaust passage is equal to or greater than a predetermined temperature, the variable valve operating mechanism is controlled so as to place at least one of the exhaust valve and the intake valve in a closed state. Thus, supply of gas that has a high oxygen concentration to the exhaust purification catalyst that is in a high-temperature state is prevented, and deterioration of the exhaust purification catalyst is suppressed.
Further, for example, in Patent Document 2, a conventional configuration is disclosed that includes, in a variable valve operating apparatus capable of continuously changing the valve opening characteristics of a valve, a valve stop mechanism that can alternatively switch an operating state of the valve between a valve working state and a valve stopped state.
The applicant is aware of the following documents, which includes the above described document, as documents related to the present invention.